From 45b57c292cd072041e20201992a0d598401d8b23 Mon Sep 17 00:00:00 2001
From: Takatoshi Kondo <redboltz@gmail.com>
Date: Thu, 18 Jun 2015 09:59:15 +0900
Subject: [PATCH] Added no default constructible classes support.

---
 include/msgpack/object.hpp     | 17 ++++++
 include/msgpack/object_fwd.hpp | 39 ++++++++++++++
 test/msgpack_cpp11.cpp         | 99 ++++++++++++++++++++++++++++++++++
 3 files changed, 155 insertions(+)

diff --git a/include/msgpack/object.hpp b/include/msgpack/object.hpp
index fe40f844..8e6ec815 100644
--- a/include/msgpack/object.hpp
+++ b/include/msgpack/object.hpp
@@ -510,6 +510,8 @@ inline T* object::convert(T* v) const
     return v;
 }
 
+#if defined(MSGPACK_USE_CPP03)
+
 template <typename T>
 inline T object::as() const
 {
@@ -518,6 +520,21 @@ inline T object::as() const
     return v;
 }
 
+#else  // defined(MSGPACK_USE_CPP03)
+
+template <typename T>
+inline typename std::enable_if<msgpack::has_as<T>::value, T>::type object::as() const {
+    return msgpack::adaptor::as<T>()(*this);
+}
+
+template <typename T>
+inline typename std::enable_if<!msgpack::has_as<T>::value, T>::type object::as() const {
+    T v;
+    convert(v);
+    return v;
+}
+
+#endif // defined(MSGPACK_USE_CPP03)
 
 inline object::object()
 {
diff --git a/include/msgpack/object_fwd.hpp b/include/msgpack/object_fwd.hpp
index ffcc7db5..99e22d0e 100644
--- a/include/msgpack/object_fwd.hpp
+++ b/include/msgpack/object_fwd.hpp
@@ -81,6 +81,33 @@ struct object_ext {
     const char* ptr;
 };
 
+
+#if !defined(MSGPACK_USE_CPP03)
+struct object;
+
+namespace adaptor {
+template <typename T>
+struct as;
+} // namespace adaptor
+
+template <typename T>
+struct has_as {
+private:
+    template <typename U>
+    static auto check(U*) ->
+        typename std::is_same<
+            decltype(msgpack::adaptor::as<U>()(std::declval<msgpack::object>())),
+            T>::type;
+    template <typename>
+    static std::false_type check(...);
+    using type = decltype(check<T>(nullptr));
+public:
+    static constexpr bool value = type::value;
+};
+
+#endif // !defined(MSGPACK_USE_CPP03)
+
+
 struct object {
     union union_type {
         bool boolean;
@@ -102,9 +129,21 @@ struct object {
 
     bool is_nil() const { return type == msgpack::type::NIL; }
 
+#if defined(MSGPACK_USE_CPP03)
+
     template <typename T>
     T as() const;
 
+#else  // defined(MSGPACK_USE_CPP03)
+
+    template <typename T>
+    typename std::enable_if<msgpack::has_as<T>::value, T>::type as() const;
+
+    template <typename T>
+    typename std::enable_if<!msgpack::has_as<T>::value, T>::type as() const;
+
+#endif // defined(MSGPACK_USE_CPP03)
+
     template <typename T>
     T& convert(T& v) const;
     template <typename T>
diff --git a/test/msgpack_cpp11.cpp b/test/msgpack_cpp11.cpp
index 6dd187cb..db3f226f 100644
--- a/test/msgpack_cpp11.cpp
+++ b/test/msgpack_cpp11.cpp
@@ -185,4 +185,103 @@ TEST(MSGPACK_USER_DEFINED, simple_buffer_enum_class_member)
     EXPECT_EQ(val1.t3, val2.t3);
 }
 
+struct no_def_con {
+    no_def_con() = delete;
+    no_def_con(int i):i(i) {}
+    int i;
+    MSGPACK_DEFINE(i);
+};
+
+namespace msgpack {
+MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS) {
+namespace adaptor {
+template <>
+struct as<no_def_con> {
+    no_def_con operator()(msgpack::object const& o) const {
+        if (o.type != msgpack::type::ARRAY) throw msgpack::type_error();
+        if (o.via.array.size != 1) throw msgpack::type_error();
+        return no_def_con(o.via.array.ptr[0].as<int>());
+    }
+};
+} // adaptor
+} // MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS)
+} // msgpack
+
+TEST(MSGPACK_NO_DEF_CON, simple_buffer)
+{
+    no_def_con val1(42);
+    msgpack::sbuffer sbuf;
+    msgpack::pack(sbuf, val1);
+    msgpack::unpacked ret;
+    msgpack::unpack(ret, sbuf.data(), sbuf.size());
+
+    no_def_con val2 = ret.get().as<no_def_con>();
+    EXPECT_EQ(val1.i, val2.i);
+}
+
+struct no_def_con_composite {
+    no_def_con_composite() = delete;
+    no_def_con_composite(no_def_con const& a):ndc(a) {}
+    no_def_con ndc;
+    MSGPACK_DEFINE(ndc);
+};
+
+namespace msgpack {
+MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS) {
+namespace adaptor {
+template <>
+struct as<no_def_con_composite> {
+    no_def_con_composite operator()(msgpack::object const& o) const {
+        if (o.type != msgpack::type::ARRAY) throw msgpack::type_error();
+        if (o.via.array.size != 1) throw msgpack::type_error();
+        return no_def_con_composite(o.via.array.ptr[0].as<no_def_con>());
+    }
+};
+} // adaptor
+} // MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS)
+} // msgpack
+
+TEST(MSGPACK_NO_DEF_CON_COMPOSITE, simple_buffer)
+{
+    no_def_con_composite val1(42);
+    msgpack::sbuffer sbuf;
+    msgpack::pack(sbuf, val1);
+    msgpack::unpacked ret;
+    msgpack::unpack(ret, sbuf.data(), sbuf.size());
+    no_def_con_composite val2 = ret.get().as<no_def_con_composite>();
+    EXPECT_EQ(val1.ndc.i, val2.ndc.i);
+}
+
+struct no_def_con_inherit : no_def_con {
+    no_def_con_inherit() = delete;
+    no_def_con_inherit(no_def_con const& a):no_def_con(a) {}
+    MSGPACK_DEFINE(MSGPACK_BASE(no_def_con));
+};
+
+namespace msgpack {
+MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS) {
+namespace adaptor {
+template <>
+struct as<no_def_con_inherit> {
+    no_def_con_inherit operator()(msgpack::object const& o) const {
+        if (o.type != msgpack::type::ARRAY) throw msgpack::type_error();
+        if (o.via.array.size != 1) throw msgpack::type_error();
+        return no_def_con_inherit(o.via.array.ptr[0].as<no_def_con>());
+    }
+};
+} // adaptor
+} // MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS)
+} // msgpack
+
+TEST(MSGPACK_NO_DEF_CON_INHERIT, simple_buffer)
+{
+    no_def_con_inherit val1(42);
+    msgpack::sbuffer sbuf;
+    msgpack::pack(sbuf, val1);
+    msgpack::unpacked ret;
+    msgpack::unpack(ret, sbuf.data(), sbuf.size());
+    no_def_con_inherit val2 = ret.get().as<no_def_con_inherit>();
+    EXPECT_EQ(val1.i, val2.i);
+}
+
 #endif // !defined(MSGPACK_USE_CPP03)